As rain-swept South Australia braces for more flooding, Josh Frydenberg has conceded what the state government has been saying since Wednesday's freak storm caused a blackout across the region.

The federal energy minister’s preliminary inquiries shows the state’s growing dependency on renewable energy was not the reason for the cascading blackouts, which have left some homes still without power four days after the unprecedented event.

A spokesman for the SA government has said it wouldn’t have mattered if the electricity was coal-fired or gas fired generated, it was the transmission lines that went down.

But Mr Frydenberg says there still needs to be a full inquiry into what happened and this will be the subject of discussions at an emergency COAG meeting between the Commonwealth and the state and territory energy ministers on Friday.

“Cleary, following the events on South Australia we need to have a real debate about the implications of the higher reliance on renewables,” Mr Frydenberg told Sky News.

SA Premier Jay Weatherill is pushing for a true national energy market, and one supporting – not punishing – renewable energy.

But Mr Frydenberg stepped up his attack on states having “ridiculously high and unrealistic” renewable energy targets,

For his own state of Victoria, it has a target of 40 per cent by 2025 when it is only generating 12 per cent through renewable energy now, while federal Labor has a “crazy” 50 per cent target without any detail.

“Clearly the states have an illusion as to the impact that renewables are having on the system,” he said.

He is confident Australia can reach the federal government’s 23.5 per cent by 2020.

Labor environment spokesman Mark Butler said he was glad the government had finally “come on to the playing field” after the prime minister and his deputy week made “cheap political points” about renewable energy.

He said it must be recognised the country can’t continue to operate the generation infrastructure, which in many cases was built the 1960s and the 1970s.

“Over the next 10 or 15 years, even if there was not a climate change imperative or a renewable energy revolution sweeping the world, Australia would have to be having a discussion now about how we were going to renew our electricity generation infrastructure,” he told Sky News.

South Australian senator Nick Xenophon said it was an unprecedented situation in his state and the nation must learn from it, because if it is not planned properly – getting the “science and physics” right – it is going to cause problems.

“The last time there was a state-wide power black-out was when the Beatles came to town in Sydney,” he told ABC television.

“I’m sure the Beatles had nothing to do with the power black-out, there weren’t too many renewables around in 1964, but we need to learn from these lessons.”